1. Field of the Invention
The present invention relates to a portable power source apparatus capable of holding circular cylindrical batteries, and for example, relates to a portable power source apparatus such as an emergency charging device equipped with a power source connector that supplies power to electronic equipment.
2. Description of the Related Art
Along with the popularity of portable electronic devices such as mobile phones and portable music players, instances where the batteries run out of charge after departure to an external destination have become common. In these situations there is a need for recharging, and emergency charging devices (also called emergency chargers, emergency re-chargers, portable emergency power packs, boosters, etc.) have been developed (for example, Japanese Laid-Open Patent Publication 2002-27674) to allow portable electronic equipment to be charged even when commercial power is locally unavailable.
Many of these types of emergency charging devices contain specially-adapted batteries. However, such a configuration makes it necessary to charge the emergency charging device in advance, and problems such as insufficient discharge capacity at the destination, or forgetting to charge the charging device can prevent its use.
To resolve these types of problems, an emergency charging device has been conceived that contains readily exchangeable off-the-shelf batteries such as AA-batteries or AAA-batteries. For example, by using rechargeable batteries such as nickel hydride batteries or nickel cadmium batteries, the batteries can be reused. In addition, even if the batteries run out of charge capacity, spare rechargeable batteries can be carried along or purchased at the destination to augment charging capacity.
Along with the distribution of this type of emergency charging device, demand for more portability of the charging device itself has developed. Specifically, it has become necessary to make even the emergency charging device conveniently portable, lightweight, and as small as possible. However, when the charging device is made smaller, protection of the internal batteries can become insufficient with associated weak points such as a case that can easily be damaged and batteries that can easily be short circuited